Viewers could soon watch post-watershed programmes before 9pm under proposals being put forward by a lobbying group for cable and satellite broadcasters including BSkyB.

Currently peak-time dramas and comedies are not allowed to be shown before the watershed, unless they are cut to remove swearing, violence and sex.

However, pay-per-view programmes and content on premium film subscription channels are allowed before the watershed because viewers have to key in a pin code before they can watch them.

The Commercial Broadcasters' Association, which represents broadcasters including Sky, UKTV and MTV, has asked the Department for Culture, Media and Sport for regulations to be changed to extend this pin protection system to cover all other shows on cable and satellite channels.

It is understood that audiences would have to enter the pin every time they wanted to watch a peak-time show before the watershed, allaying parents' fears that such a move could mean a relaxing of the 9pm boundary on language, taste and decency.

This means, for example, if Sky wanted to put post-watershed drama Mad Dogs on in daytime it could do so without re-editing as viewers would have to punch in their pin code in order to watch it.

The proposed overhauling of pin protection rules would not cover adult channels.

The system would be on a voluntary basis and Coba believes it "will provide more choice for audiences, while offering secure and established protection processes".

Coba has put the plan in its submission to the DCMS for the communications review taking place ahead of a new communications bill, saying: "To open up new potential ways of making content available, regulations should allow broadcasters on a voluntary basis to choose to make other appropriate forms of linear content available via pin protection."

Such a system is already in place for online catchup TV services.

The Coba executive director, Adam Minns, said: "The system of pin protection is well established in the UK. It has proven to be effective technically and is something with which audiences are familiar – it is now used on a range of services.

"At the same time, it provides consumer protection that is arguably more effective than the watershed regime. Extending such a regime to other services could potentially encourage innovative new forms of content delivery."

It is expected that such a move would need a consultation by Ofcom as it would require changes to the media regulator's broadcasting code.

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